Medical devices with detachable pivotable jaws

ABSTRACT

Medical systems, devices and methods are provided for engaging tissue, e.g. for clipping tissue, closing a perforation or performing hemostasis. Generally, the medical system including a housing, first and second jaws rotatable relative to the housing, first and second links pivotally attached to the jaws, and a driver. The housing, first and second jaws, and first and second links form a linkage mechanism that allows the jaws to engage tissue and be left in vivo.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation-In-Part of U.S. patent applicationSer. No. 12/971,873 filed on Dec. 17, 2010, and also claims the benefitof U.S. Provisional Patent Application Ser. No. 61/391,875 filed on Oct.11, 2010. All of the foregoing applications are hereby incorporated byreference.

BACKGROUND

Conventionally, a clip may be introduced into a body cavity through anendoscope to grasp living tissue of a body cavity for hemostasis,marking, and/or ligating. Such clips are often known as surgical clips,endoscopic clips, hemostasis clips and vascular clips. In addition,clips are now being used in a number of applications related togastrointestinal bleeding such as peptic ulcers, Mallory-Weiss tears,Dieulafoy's lesions, angiomas, post-papillotomy bleeding, and smallvarices with active bleeding. Clips have also been attempted for use inclosing perforations in the stomach

Gastrointestinal bleeding is a somewhat common and serious conditionthat is often fatal if left untreated. This problem has prompted thedevelopment of a number of endoscopic therapeutic approaches to achievehemostasis such as the injection of sclerosing agents and contactthermo-coagulation techniques. Although such approaches are ofteneffective, bleeding continues for many patients and corrective surgerytherefore becomes necessary. Because surgery is an invasive techniquethat is associated with a high morbidity rate and many other undesirableside effects, there exists a need for highly effective, less invasiveprocedures.

Mechanical hemostatic devices such as clips have been used in variousparts of the body, including gastrointestinal applications. One of theproblems associated with conventional hemostatic devices and clips,however, is that many devices are not strong enough to cause permanenthemostasis. Further, clips have also been attempted for use in closingperforations in the stomach or gastrointestinal structures, butunfortunately traditional clips suffer from difficult placement and thecapability to grasp a limited amount of tissue, potentially resulting inincomplete closure.

SUMMARY

The invention may include any of the following aspects in variouscombinations and may also include any other aspect described below inthe written description or in the attached drawings.

In a first aspect, a medical device is provided for engaging tissue, themedical device including a housing, first and second jaws, first andsecond links, and a driver. The housing defines an internal passagewayand a longitudinal axis extending between proximal and distal ends ofthe housing. The housing also defines a jaw guide surface, a first linkguide surface and a second link guide surface, each of the guidesurfaces extending longitudinally between proximal and distal ends ofthe guide surfaces. The first jaw is slidably and pivotally connected tothe housing, and has proximal and distal ends. The first jaw is slidablyreceived within the internal passageway for longitudinal movement alongthe jaw guide surface. The second jaw is slidably and pivotallyconnected to the housing, and has proximal and distal ends. The secondjaw is slidably received within the internal passageway for longitudinalmovement along the jaw guide surface. The first link has first andsecond ends. The first end is pivotally attached to the first jaw, andthe second end is slidably and pivotally attached to the housing forlongitudinal movement along the first link guide surface. The secondlink has first and second ends. The first end is pivotally attached tothe second jaw, and the second end is slidably and pivotally attached tothe housing for longitudinal movement along the second link guidesurface. The driver is operatively connected to the first and secondjaws, whereby longitudinal movement of the driver moves the first andsecond jaws longitudinally along the jaw guide surface and moves thesecond ends of the first and second links along the first and secondlink guide surfaces. Longitudinal movement of the driver rotates thefirst and second jaws relative to the housing when the second ends ofthe first and second links reach the distal ends of the first and secondlink guide surfaces.

According to more detailed aspects, the proximal ends of the first andsecond jaws are slidably and pivotally attached to the housing.Preferably, the proximal ends are pivotally attached to the housingabout a shared jaw pivot axis. A jaw pivot pin may be used to pivotallyconnect the proximal ends of both the first and second jaws to thehousing. The jaw guide surface is defined by opposing jaw slots formedin the housing, the opposing jaw slots receiving opposing ends of thejaw pivot pin. Preferably, the jaw guide surface extends longitudinallyand parallel to the central axis. The jaw guide surface may be locatedbetween the first and second link guide surfaces. The first ends of thefirst and second links are pivotally attached at a midpoint of the firstand second jaws, respectively, while the second ends of the first andsecond links are slidably and pivotally connected to the housing.

According to further detailed aspects, the driver is engaged with theproximal ends of the first and second jaws when the driver is moveddistally. The driver is engaged with the second ends of the first andsecond links when the driver is moved proximally. Preferably, the driverincludes a distal end for engaging the first and second jaws, the distalend of the driver including a first flange which engages the proximalend of the first jaw and is shaped to permit rotation of the first jawrelative to the first flange while engaged, the distal end of the driverincluding a second flange which engages the proximal end of the secondjaw and is shaped to permit rotation of the second jaw relative to thesecond flange while engaged. The driver extends longitudinally to aposition located proximal to the second ends of the first and secondlinks.

According to still further detailed aspects, the first and second jawsare longitudinally slidable between an extended position and a retractedposition, and the housing is structured to block rotation of the firstand second jaws when in their retracted positions, and the housing isstructured to permit rotation of the first and second jaws when in theirextended positions. The first and second links are also longitudinallyslidable between an extended position and a retracted position, and atthe same time or alternatively, the housing is structured to blockrotation of the first and second links when in their retractedpositions, and the housing is structured to permit rotation of the firstand second links when in their extended positions. The housing, thefirst link, and the first jaw are pivotable relative to each other, andthe housing, the second link, and the second jaw are pivotable relativeto each other, and further the second ends of the first and second linksare longitudinally slidable relative to the proximal ends of the firstand second jaws, whereby the distance between the second ends andproximal ends determines the rotation of the first and second jawsbetween a closed configuration and an open configuration. The device mayalso include an elongate drive wire selectively connected to the driverfor longitudinal movement therewith, and an elongate tubular member(e.g. a catheter) selectively connected to the housing. Sufficientproximal translation of the drive wire disconnects the driver from thedrive wire and the housing from the elongate tubular member.

According to more detailed aspects, the device may also include a firstlink pivot pin that pivotally connects the second end of the first linkto the housing, and a second link pivot pin that pivotally connects thesecond end of the second link to the housing. The first link guidesurface is defined by opposing first link slots formed in the housing,and the second link guide surface is defined by opposing second linkslots formed in the housing, wherein the opposing first link slotsreceive opposing ends of the first link pivot pin, and wherein theopposing second link slots receive opposing ends of the second linkpivot pin.

In a second aspect, a method is provided for clamping tissue. The methodincludes providing a medical device comprising a housing, first andsecond jaws, first and second links, and a driver, wherein the first andsecond jaws are slidably and pivotally connected to the housing, thefirst and second links are slidably and pivotally connected to thehousing, the first and second links are pivotally attached to the firstand second jaws, respectively, and the driver is operatively connectedto the first and second jaws. The driver is advanced distally totranslate the first and second jaws and the first and second linksdistally relative to the housing. The distal translation of the firstand second links is limited or blocked while further advancing thedriver distally to rotate the first and second jaws relative to thehousing. The driver is retracted proximally to rotate the first andsecond jaws relative to the housing. According to more detailed aspects,the medical device may further comprise an elongated drive wireselectively connected to the driver for longitudinal movement therewith,and the drive wire may be detached from the driver.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings incorporated in and forming a part of thespecification illustrate several aspects of the present invention, andtogether with the description serve to explain the principles of theinvention. In the drawings:

FIG. 1 is a top view of a medical system having a medical device forengaging tissue, constructed in accordance with the teachings of thepresent invention;

FIG. 2 is a top view similar to FIG. 1, but showing the outer structuresin dotted lines and the interior sections in solid lines and partialcross-section;

FIG. 3 is a side view of the medical system and device depicted in FIG.1;

FIG. 4 is a side view similar to FIG. 3, but showing the outerstructures in dotted lines and the interior structures in solid linesand partial cross section

FIG. 5 is a front perspective view of interior structures of the medicalsystem and device depicted in FIGS. 1-4;

FIG. 6 is a rear perspective view of interior structures of the medicalsystem and device depicted in FIGS. 1-4;

FIGS. 7-11 are side views showing operation of the medical system anddevice depicted in FIGS. 1-4;

FIGS. 12 and 13 are top views, partially in cross-section, depictingoperation of the medical system and device depicted in FIGS. 1-4; and

FIGS. 14 and 15 are cross-sectional views showing operation of themedical system depicted in FIGS. 1-4.

DETAILED DESCRIPTION

The terms “proximal” and “distal” as used herein are intended to have areference point relative to the user. Specifically, throughout thespecification, the terms “distal” and “distally” shall denote aposition, direction, or orientation that is generally away from theuser, and the terms “proximal” and “proximally” shall denote a position,direction, or orientation that is generally towards the user.

An exemplary medical system 20 having a medical device 40 for engagingtissue T (FIG. 11) is shown in FIGS. 1 through 4. The medical system 20and device 40 are generally sized and structured for operation throughthe working channel of an endoscope (not shown) or other scope, althoughthe system 20 and device 40 may also be used alone or in conjunctionwith other elongate devices such as catheters, fiber-optic visualizationsystems, needles and the like. Generally, the medical system 20 includesa drive wire 22 slidably housed within the distal end 23 of a catheter24 for selective connection to, and operation of, the medical device 40.As will be described in further detail herein, the medical device 40generally includes a housing 42 having a first jaw 44 and a second jaw46 pivotally connected thereto for engaging the tissue T. Generally, thejaws 44, 46 have been shown as forming grasping forceps, although thejaws are intended to be used to clip tissue, e.g. to close an opening orfor hemostasis. Accordingly, it will be recognized that the shape andstructure of the jaws may take many forms and serve many purposes andfunctions, all in accordance with the teachings of the presentinvention.

In the medical system 20, the drive wire 22 slidably extends through thecatheter 24. Although the term “wire” is used to refer to the drive wire22, it will be recognized that any elongate control member capable oftransmitting longitudinal force over a distance (such as is required intypical endoscopic, laparoscopic and similar procedures) may be used,and this includes plastic rods or tubes, single filament ormulti-filament wires and the like. The drive wire 22 should also becapable of properly transmitting a rotational/torsional force from theproximal end to the distal end to rotate the medical device 40 and jaws44, 46, and thus it is currently preferred that the drive wire 22 isformed from nitinol (e.g. a nitinol wire) or other superelastic alloy.

A connection block 26 is slidably fitted within the distal end 23 of thecatheter 24 and defines a bore 28 therethrough which slidably receivesthe drive wire 22. The exterior of the connection block 26 includes arecessed portion 27, and two pins 30 (e.g., formed from stainless steelwire) are connected to the catheter 24 and positioned within therecessed portion 27 (i.e. between proximal and distal flanges definingthe recessed portion 27) to limit the longitudinal movement of theconnection block 26.

A distal end of the drive wire 22 defines a distal head 32 that is sizedlarger than the drive wire 22, and likewise larger than the bore 28 inthe connection block 26. As will be described later herein, the distalhead 32 is used to slide the connection block 26 within the catheter 24to disconnect the medical device 40 from the medical system 20. As alsoseen in FIGS. 1-4, the housing 42 of the medical device 40 is a tubularmember defining an interior space 43. A proximal end of the housing 42frictionally receives a distal end of the connection block 26 within theinterior space 43 for selective connection therewith.

The internal passageway 43 of the housing 42 also receives the first andsecond jaws 44, 46 and a driver 48 which is used to interconnect thedrive wire 22 to the jaws 44, 46. As best seen in FIG. 5, the first andsecond jaws 44, 46 include distal ends 60, 62 that are structured tograsp and engage tissue, which have a talon shape as disclosed in61/141,934 filed Dec. 31, 2008, the disclosure of which is incorporatedherein by reference in its entirety. Generally, distal translation ofthe driver 48 causes the first and second jaws 44, 46 to rotateoutwardly away from each other, while proximal retraction of the driver48 causes the first and second jaws 44, 46 to rotate inwardly toward oneanother.

As best seen in FIGS. 1, 2 and 5-6, the driver 48 has a proximal portionwhich defines a socket 50 sized to receive enlarged distal head 32 ofthe drive wire 22. At the proximal entrance of the socket 50, twodeflectable locking tabs 52 are formed which rotate relative to theremainder of the driver 48 to increase or decrease the size of thesocket 50. The locking tabs 52 may be separately formed and pivotallyattached to the driver 48, or may be integrally formed with the driver48 and formed of a resilient material which flexes to permit rotation ofthe locking tabs 52 radially inwardly and radially outwardly. Preferablythe locking tabs 52 are plastically deformable, such that they may belocked to the drive wire 22 or to the housing 42, as discussed furtherherein.

As best seen in FIGS. 5-6, a distal portion of the driver 48 defines atwo L-shaped flanges 56, 58 for engaging and operating the jaws 44, 46.The inner surface of flange 56 engages a proximal end 66 of jaw 46,while the inner surface of flange 58 engages a proximal end 64 of jaw44. The flanges 56, 58 are shaped to permit rotation of the proximalends 64, 66 of the jaws 44, 46 relative to the flanges 56, 58 whileengaged therewith. While the flanges 56, 58 and proximal ends 64, 66have been shown as squared-off (so that they firmly engage in the fullyopen, and fully closed, positions), the mating surfaces may be roundedor otherwise shaped to promote rotation between the flanges 56, 58 andthe proximal ends 64, 66 of the jaws 44, 46.

The proximal ends 64, 66 of jaws 44, 46 are pivotally attached to thehousing 42 directly via a pin 49 which extends through the proximal ends64, 66 and through opposing jaw slots 86 formed in the housing, as bestseen in FIGS. 3-4. By virtue of the jaw slots 86, the jaws 44, 46 arethus both pivotally, and slidably, attached to the housing 42. Theopposing jaw slots 86 thus act and define a jaw guide surface of thehousing 42 which guides longitudinal movement of the jaws 44, 46relative to the housing. The distal ends of the jaw slots 86 also serveto restrict the longitudinal movement of the jaws 44, 46 relative to thehousing 42. It will be recognized that the jaw guide surface could alsobe formed by channels, recesses or other structures formed into thehousing 42, instead of, or in conjunction with, the jaw slots 86. Duringassembly, the slots allow the pins of the device 40 to be inserted afterthe jaws, links and driver are positioned with the housing, and theslots may later be covered with a sleeve, strip, secondary housing orother material if desired.

Turning back to FIGS. 5 and 6, the first and second jaws 44, 46 are alsoindirectly connected to the housing 42 via first and second links 68,70, respectively. Distal ends of the first and second links 68, 70 arepivotally attached to first and second jaws 44, 46 via pivots 81. Thepivotal connections (pivots 81) are formed at a midpoint of the firstand second jaws 44, 46, i.e. anywhere between the proximal ends 66, 68and the distal ends 60, 62 of the first and second jaws 44, 46. Theproximal ends of the first and second links 68, 70 are slidably andpivotally attached to the housing 42 via two pins 80. In particular, andas best seen in FIGS. 3-4, the housing 42 defines opposing first linkslots 82 that are sized and positioned to receive the pin 80 of thefirst link 68, as well as opposing second link slots 84 that are sizedand positions to receive the pin 80 of the second link 70. In FIGS. 1-2,the opposing first link slots 82 are individually identified byreference numerals 82 a and 82 b. Accordingly, the opposing first andsecond link slots 82, 84 act and define first and second link guidesurfaces of the housing 42 which guide longitudinal movement of thefirst and second links 68, 70 relative to the housing 42. As with thejaw guide surface, the first and second link guide surfaces could alsobe formed by channels, recesses or other structures formed into thehousing 42, instead of, or in conjunction with, the first and secondlink slots 82, 84.

The driver 48 extends between the proximal ends of the first and secondlinks 68, 70, and engages the proximal ends 64, 66 of the first andsecond jaws 44, 46 to first expose and then open the jaws 44, 46, asshown in FIGS. 5 and 6. At the same time, the proximal ends of the links68, 70 and their pins 80 are located such that proximal retraction ofthe driver 48 (via drive wire 22) causes the outer surface of theL-shaped flanges 56, 58 to engage the pins 80 (or links 68, 70) forretraction and closing of the jaws 44, 46, as will be described infurther detail below. It can thus be seen that the jaw guide surface ofslot 86 is located between the first and second link guide surfaces ofslots 82, 84 (which are above and below the slot 86), as best seen inFIGS. 3-4.

The internal passageway 43 of the housing 42 extends through the distalend of the housing 42, and it is through this passageway 43 that thefirst and second jaws 44, 46 can extend. Additionally, as shown in FIGS.1-4, the housing 42 defines opposing slots 45 which are sized to permitthe first and second jaws 44, 46 and the first and second links 68, 70to pass therethrough when they rotate radially outwardly. Accordingly,it is also clear from FIGS. 1 and 2 that the housing 42 serves to blockrotation of the first and second links 68, 70 when they are entirely orpartially contained within the internal passageway 43 of the housing 42.Suitable plastics for forming the housing include, but are not limitedto, polytetrafluorethylene (PTFE), expanded polytetrafluorethylene(EPTFE), polyethylene ether keytone (PEEK), polyvinylchloride (PVC),polycarbonate (PC), polyamide, polyimide, polyurethane, polyethylene(high, medium or low density), and suitable metals include stainlesssteel, nitinol and similar medical grade metals and alloys.

Turning to the sequence of FIGS. 7-11, operation of the medical device40 will now be described. As shown in FIG. 7, the first and second jaws44, 46 are shown in a retracted position where they are substantiallycontained within the housing 42. Depending on the application, thedistal ends 60, 62 of the jaws 44, 46 may slightly project from thedistal end of the housing 42 in their retracted positions, or they maybe entirely positioned within the housing 42. When the drive wire 22 istranslated distally (to the left on the page in FIG. 7) the distal head32 engages the driver 48, which in turn engages the proximal ends 64, 66of the jaws 44, 46 (via the driver's flanges 56, 58 (FIGS. 5-6)),causing the jaws 44, 46 to slide distally through and out of the housing42, as shown in FIG. 8. As previously mentioned, this longitudinalmovement is guided by the jaw guide surface of jaw slot 86 (receivingpin 49), and the link guide surfaces of link slots 82, 84 (receivingpins 80) which slidably and pivotally connect the jaws 44, 46 to thehousing 42.

As shown in FIG. 8, the first and second jaws 44, 46 have an extendedposition where the jaws substantially project from a distal end of thehousing 42. In this extended position, the pins 80 at the proximal endsof the first and second links 68, 70 have reached the end of their slots82, 84, while the pin 49 at the proximal ends 64, 66 of the jaws 44, 46have not reached the end of slot 86. Accordingly, it will be seen thatfurther distal advancement of drive wire 22, and hence the driver 48,causes the proximal ends 64, 66 of jaws 44, 46 to continue movingdistally (to the left on the page), while the links 68, 70 inducerotation of the jaws 44, 46 away from each other, as shown in FIG. 9.Eventually, the pin 49 reaches the end of jaw slot 86, at which pointthe jaws 44, 46 are fully open. The jaws 44, 46 have been shown rotatingabout 75°, thus forming a 150° opening between them, however the housing42 and its slots may be sized to permit rotation through a full 90° ormore, thus forming at least a 180° between them. The slots 45 in thehousing 42 are sized to permit the rotation of the jaws 44, 46 and links68, 70 out of the housing, and these slots 45 may also be used to limitthe rotation thereof, in addition to or separately from the sizing ofthe slots 82, 84, 86. It will therefore be seen that the distancebetween the pins 80 (at the ends of the first and second links 68, 70)and the proximal ends 64, 66 of the jaws 44, 46 determines the rotationof the first and second jaws between a closed configuration and an openconfiguration.

In the tissue receiving configuration (open configuration) shown in FIG.9, the medical device 40 and its jaws 44, 46 may be positioned adjacenttissue T. As shown in FIG. 10, the tissue T may be placed between thefirst and second jaws 44, 46 and the jaws 44, 46 rotated back towardstheir position shown in FIG. 8. The tissue T has been shown as a singlelayer, although multiple layers may be clipped between the jaws 44, 46.Generally, proximal retraction of the drive wire 22 and the driver 48causes the flanges 56, 58 of the driver 48 to engage the pins 80 at theproximal ends of the links 68, 70. In particular, as also clear fromFIGS. 5 and 6, the flange 56 will engage pin 80 of the first link 68,and flange 58 will engage pin 80 of second link 70. As the links 68, 70are pulled proximally (to the right on the page) the housing 42 presseson the links 68, 70 (and/or the jaws 44, 46) and causes them to rotatetowards each other to grasp the tissue T therebetween. Depending ontheir orientation relative to the patient and the ground, the jaws 44,46 may also naturally collapse towards each other. As shown in FIG. 11,further proximal retraction of the drive wire 22 and driver 48 willcause the jaws 44, 46 to move longitudinally in a proximal direction (tothe right on the page in FIG. 11).

In order for the medical device 40 to serve as a clip and maintain itsgrasp on the tissue T, or to maintain the clipping of two layers oftissue against each other, the jaws 44, 46 may be locked in position andthe drive wire 22 of the medical system 20 disconnected from the medicaldevice 40. As shown in FIG. 12, the interior of the housing 42 alsodefines a driver guide surface 88 (which guides the driver 48) that hasa proximal portion 88 p and a distal portion 88 d. The proximal portion88 p of the driver guide surface 88 has a width (measured up and down onthe page in FIG. 12) that is greater than a width of the distal portion88 d of the driver guide surface 88. The driver guide surface 88 may beformed by opposing surfaces or C-shaped channels in the housing 42. Thetransition between the proximal portion 88 p and distal portion 88 ddefines a shoulder 89, and namely two shoulders 89 a, 89 b on opposingsides of the housing 42. The shoulders 89 a, 89 b are sized andpositioned to engage the locking tabs 52 located on the driver 48.

As shown in FIG. 12, when the driver 48 is located within the distalportion 86 d of the third guide surface 86, the locking tabs 52 areforced radially inwardly into firm frictional engagement with theenlarged head 32 and/or the drive wire 22. Stated another way, thesocket 50 formed by the driver 48 that receives the distal head 32 hasan entrance which is narrowed by the inward deflection of the lockingtabs 52. In this state depicted in FIG. 12, the drive wire 22 is firmlyengaged with the driver 48 and hence the first and second jaws 44, 46.When the drive wire 22 and driver 48 are retracted proximally, forexample upon grasping tissue as shown in FIG. 11, the proximal end ofthe driver 48 is received within the proximal portion 88 p of the thirdguide surface 88 which has a larger width that permits outward movementof the locking tabs 52. Accordingly, in the state depicted in FIG. 13,the locking tabs 52 may be loosely and detachably connected to thedistal head 32 of the drive wire 22. As such, further proximal movementof the drive wire 22 and its distal head 32 may be used to withdraw thedistal head 32 from the socket 50 of the driver 48. At the same time,the locking tabs 52 move radially outwardly and into engagement with theshoulders 89 a, 89 b to lock the device 40 in a state where the tissue Tis clipped between the jaws 44, 46. The tabs 52 may plastically deformto this outward position to maintain the closed configuration of thejaws. In the event the natural elasticity of the tissue T tends to pullthe jaws 44, 46 out from the housing towards their extended position,the locking tabs 52 will abut the shoulders 89 of the driver guidesurface of the housing 42 to prevent further distal movement or rotationof the jaws 44, 46.

Turning now to FIGS. 14 and 15, upon still further proximal retractionof the drive wire 22 and distal head 32 (to the right on the page), theenlarged distal head 32 (or other enlarged portion of the drive wire 22)will abut the connection block 26, which is slidably fitted within thedistal end 23 of the catheter 24. Sufficient proximal force on the drivewire 22 will overcome the frictional fit between the connection block 26and the proximal end of the housing 42, thus moving the connection block26 proximally to retract the connection block 26 within the tubularconnector 24, as shown in FIG. 15. The catheter 24 can be used toprovide a counterforce on the housing 42 while proximally retracting thedrive wire 22 and connection block 26. Accordingly, the drive wire 22,catheter 24 and connection block 26 may be fully disconnected from themedical device 40, thereby leaving the first and second jaws 44, 46 andthe housing 42 in a state having the tissue T clipped between the jaws44, 46 and retained in vivo. The connection block 26 is retained at thedistal end 23 of the catheter 24 via the pins 30, which are positionedwithin the recessed area 27 to engage the proximal and distal ends ofthe connection block 26 and limit its longitudinal movement.

The elongate catheter 24 (or other elongate tubular member such as asheath, tube, scope or the like), which slidably encases the drive wire22, extends proximally therealong to a proximal end of the system 20,and has a length suitable for placing the device 40 at any desirelocation within the body, while the proximal ends of drive wire 22 andcatheter 24 are positioned outside of the body for use by the medicalprofessional. Control handles (not shown) for controlling relativetranslation of the drive wire 22 and catheter 24 are well known in theart, and may be employed at the proximal end of the system 20.Additional embodiments of the connection/disconnection mechanisms andthe medical system 20 may be found in copending U.S. Appl. No.61/391,878 and Appl. No. 61/391,881, the disclosures of which are herebyincorporated by reference in their entirety.

The foregoing description of various embodiments of the invention hasbeen presented for purposes of illustration and description. It is notintended to be exhaustive or to limit the invention to the preciseembodiments disclosed. Numerous modifications or variations are possiblein light of the above teachings. The embodiments discussed were chosenand described to provide the best illustration of the principles of theinvention and its practical application to thereby enable one ofordinary skill in the art to utilize the invention in variousembodiments and with various modifications as are suited to theparticular use contemplated. All such modifications and variations arewithin the scope of the invention as determined by the appended claimswhen interpreted in accordance with the breadth to which they arefairly, legally, and equitably entitled.

The invention claimed is:
 1. A medical device for engaging tissue, themedical device comprising: a housing defining an internal passageway anda longitudinal axis extending between proximal and distal ends of thehousing, the housing defining a jaw guide surface, a first link guidesurface and a second link guide surface, each of the guide surfacesextending longitudinally between proximal and distal ends of theirrespective guide surfaces; a first jaw slidably and pivotally connectedto the housing, the first jaw having proximal and distal ends, the firstjaw slidably received within the internal passageway for longitudinalmovement along the jaw guide surface; a second jaw slidably andpivotally connected to the housing, the second jaw having proximal anddistal ends, the second jaw slidably received within the internalpassageway for longitudinal movement along the jaw guide surface; afirst link elongated in the longitudinal direction between first andsecond ends of the first link, the first end pivotally attached to thefirst jaw, the second end slidably and pivotally attached to the housingfor longitudinal movement along the first link guide surface; a secondlink elongated in the longitudinal direction between first and secondends of the second link, the first end pivotally attached to the secondjaw, the second end slidably and pivotally attached to the housing forlongitudinal movement along the second link guide surface; and a driveroperatively connected to the first and second jaws, longitudinalmovement of the driver moving the first and second jaws longitudinallyalong the jaw guide surface and moving the second ends of the first andsecond links along the first and second link guide surfaces,longitudinal movement of the driver rotating the first and second jawsrelative to the housing when the second ends of the first and secondlinks reach the distal ends of the first and second link guide surfaces.2. The medical device of claim 1, wherein the proximal ends of the firstand second jaws are slidably and pivotally attached to the housing. 3.The medical device of claim 2, wherein the proximal ends of the firstand second jaws are pivotally attached to the housing about a shared jawpivot axis.
 4. The medical device of claim 3, further comprising a jawpivot pin that pivotally connects the proximal ends of both the firstand second jaws to the housing.
 5. The medical device of claim 4,wherein the jaw guide surface is defined by opposing jaw slots formed inthe housing, the opposing jaw slots receiving opposing ends of the jawpivot pin.
 6. The medical device of claim 1, wherein the jaw guidesurface extends longitudinally and parallel to the central axis.
 7. Themedical device of claim 1, wherein the jaw guide surface is locatedbetween the first and second link guide surfaces.
 8. The medical deviceof claim 1, wherein the first ends of the first and second links arepivotally attached at a longitudinal midpoint of the first and secondjaws, respectively.
 9. The medical device of claim 1, wherein the secondends of the first and second links are slidably and pivotally connectedto the housing.
 10. The medical device of claim 1, wherein the driver isengaged with the proximal ends of the first and second jaws when thedriver is moved distally.
 11. The medical device of claim 1, wherein thedriver is directly engaged with the second ends of the first and secondlinks for movement therewith only when the driver is moved proximally.12. The medical device of claim 1, wherein the driver includes a distalend for engaging the first and second jaws, the distal end of the driverincluding a first flange which engages the proximal end of the first jawand is shaped to permit rotation of the first jaw relative to the firstflange while engaged, the distal end of the driver including a secondflange which engages the proximal end of the second jaw and is shaped topermit rotation of the second jaw relative to the second flange whileengaged.
 13. The medical device of claim 1, wherein the driver extendslongitudinally to a position located proximal to the second ends of thefirst and second links.
 14. The medical device of claim 1, wherein thefirst and second jaws are longitudinally slidable between an extendedposition and a retracted position, and wherein the housing is structuredto block rotation of the first and second jaws when in their retractedpositions, and the housing is structured to permit rotation of the firstand second jaws when in their extended positions.
 15. The medical deviceof claim 1, wherein the first and second links are longitudinallyslidable between an extended position and a retracted position, andwherein the housing is structured to block rotation of the first andsecond links when in their retracted positions, and the housing isstructured to permit rotation of the first and second links when intheir extended positions.
 16. The medical device of claim 1, wherein thehousing, the first link, and the first jaw are pivotable relative toeach other, and wherein the housing, the second link, and the second jaware pivotable relative to each other, and wherein the second ends of thefirst and second links are longitudinally slidable relative to theproximal ends of the first and second jaws, whereby the distance betweenthe second ends and proximal ends determines the rotation of the firstand second jaws between a closed configuration and an openconfiguration.
 17. The medical device of claim 1, further comprising anelongate drive wire selectively connected to the driver for longitudinalmovement therewith, and further comprising an elongate tubular memberselectively connected to the housing.
 18. The medical device of claim17, wherein sufficient proximal translation of the drive wiredisconnects the driver from the drive wire and the housing from theelongate tubular member.
 19. The medical device of claim 1, furthercomprising a first link pivot pin that pivotally connects the second endof the first link to the housing, and further comprising a second linkpivot pin that pivotally connects the second end of the second link tothe housing, and wherein the first link guide surface is defined byopposing first link slots formed in the housing, and wherein the secondlink guide surface is defined by opposing second link slots formed inthe housing, and wherein the opposing first link slots receive opposingends of the first link pivot pin, and wherein the opposing second linkslots receive opposing ends of the second link pivot pin.
 20. A methodfor operating a medical device, the method comprising the steps of:providing the medical device comprising a housing, first and secondjaws, first and second links, and a driver, wherein the first and secondjaws are slidably and pivotally connected to the housing, the first andsecond links are slidably and pivotally connected to the housing, thefirst and second links are pivotally attached to the first and secondjaws, respectively, and the driver is operatively connected to the firstand second jaws; advancing the driver distally relative to the housingto translate the first and second jaws and the first and second linksdistally relative to the housing; limiting the distal translation of thefirst and second links while further advancing the driver distallyrelative to the housing to rotate the first and second jaws in a firstdirection relative to the housing; and retracting the driver proximallyto rotate the first and second jaws in a second direction relative tothe housing.
 21. The method of claim 20, wherein the medical devicefurther comprises an elongated drive wire selectively connected to thedriver for longitudinal movement therewith, and further comprising thestep of detaching the drive wire from the driver.